Driver to use a motor encoder on a supported serial device. More...

#include <encoder_driver.h>

Inheritance diagram for EncoderDriver:

Public Member Functions
	EncoderDriver (bosch_hardware_interface *hw, uint8_t encoder1_pin, uint8_t encoder2_pin)
	Constructor: also constructs an encoder object on the serial device itself.
	EncoderDriver (bosch_hardware_interface *hw, uint8_t encoder_id)
	Constructor: does not construct a new object on the serial device but uses the one defined by encoder_id.
uint8_t	getDeviceAddress (void)
uint8_t	getEncoderID ()
	Getter method to get the encoder id of the object on the connected serial device.
int64_t	getPosition ()
	Gets the current motor encoder position from the connected hardware device.
bool	initialize ()
	Initializes the driver and the connected hardware.
void	invertOutput ()
	Inverts the encoder output.
bool	setPosition (int32_t position)
	Sets the current motor encoder position to position.
	~EncoderDriver ()
Private Attributes
uint8_t	_encoder1_pin
uint8_t	_encoder2_pin
uint8_t	_encoder_id
int32_t	_last_position
int64_t	_overflow
int	invert_

Detailed Description

Driver to use a motor encoder on a supported serial device.

This class enables the user to create an instance of an encoder on the connected serial device itself. The device will keep track of the encoder value using external interrupts if available on the selected pin. To contruct the encoder object the user needs to define two pins to be used by the device. These pins will automatically enable the internal pullup resistor and expect the connected encoder to pull the input to ground or drive in both directions. It is highly recommended to use a pin with external interrupt support at least for encoder1_pin. If not, the encoder object will need to be polled frequently to detect any changes. See http://www.pjrc.com/teensy/td_libs_Encoder.html for more information

Definition at line 64 of file encoder_driver.h.

Constructor & Destructor Documentation

EncoderDriver::EncoderDriver	(	bosch_hardware_interface *	hw,
		uint8_t	encoder1_pin,
		uint8_t	encoder2_pin
	)

Constructor: also constructs an encoder object on the serial device itself.

Note:: the maximum number of encoder objects is limited to 16 even after destruction of objects

Parameters:

hw	defines where the serial device is mounted like /dev/ttyACM0
encoder1_pin	first encoder pin on the serial device. This should be a pin supporting external interrupts
encoder2_pin	second encoder pin on the serial device.

Definition at line 41 of file encoder_driver.cpp.

EncoderDriver::EncoderDriver	(	bosch_hardware_interface *	hw,
		uint8_t	encoder_id
	)

Constructor: does not construct a new object on the serial device but uses the one defined by encoder_id.

Parameters:

hw	defines where the serial device is mounted like /dev/ttyACM0

Definition at line 81 of file encoder_driver.cpp.

EncoderDriver::~EncoderDriver ( )

Definition at line 99 of file encoder_driver.cpp.

Member Function Documentation

uint8_t EncoderDriver::getDeviceAddress ( void ) [virtual]

Implements bosch_drivers_common::sensor_driver.

Definition at line 118 of file encoder_driver.cpp.

uint8_t EncoderDriver::getEncoderID ( )

Getter method to get the encoder id of the object on the connected serial device.

Returns:: encoder id on the serial device [0..15]

Definition at line 145 of file encoder_driver.cpp.

int64_t EncoderDriver::getPosition ( )

Gets the current motor encoder position from the connected hardware device.

Note:: Make sure to call getPosition at least every 1 billion encoder ticks for the connected hardware works with a int32_t. An overflow is handles by this function